A reputed mobster who whined about getting “whacked” – by falling concrete – to avoid jail time was sentenced Wednesday to four months behind bars for being part of a mob effort to control New York and North Jersey’s garbage-carting industry.

Robert Franco, 51, of White Plains, tried to get out of jail time by recently claiming in legal papers that he still suffers terrible pain from a 2003 car accident and from getting whacked in the head four years ago by a chunk of falling concrete.

But the feds said the reputed Genovese soldier and nephew of ringleader Carmine “Papa Smurf” Franco is not a very wise guy – and didn’t deserve a break.

They said he was stealing recyclable cardboard trash for the mob when the concrete fell from elevated tracks in The Bronx and struck him. They know, because the blockhead was unknowingly under FBI surveillance.

Franco afterward the sentencing declined comment, but his lawyer, Richard Ma, claimed in court that “the [previous] mention of injuries was not for leniency in sentencing.”

Franco claimed in court filings last month that he can’t cut it in prison because he “walks with a limp” from the car accident and “still experiences migraine headaches” from the falling-concrete accident, which left him with a “concussion” and required “18 stitches” to his head.